import datetime
import urllib
import os

from google.appengine.api import users
from google.appengine.ext import db
from google.appengine.ext import webapp
from google.appengine.ext.webapp import template
from google.appengine.ext.webapp.util import run_wsgi_app

class Greeting(db.Model):
    author = db.UserProperty()
    content = db.StringProperty(multiline=True)
    date = db.DateTimeProperty(auto_now_add=True)

def guestbook_key(guestbook_name=None):
    return db.Key.from_path('Guestbook', 
            guestbook_name or 'default_guestbook')

class MainPage(webapp.RequestHandler):
    def get(self):
        self.response.out.write("<html><body>")
        guestbook_name = self.request.get("guestbook_name")

        greetings_query = Greeting.all().ancestor(
                guestbook_key(guestbook_name)).order('-date')
        greetings = greetings_query.fetch(10)

        if users.get_current_user():
            url = users.create_logout_url(self.request.uri)
            url_linktext = 'Logout'
        else:
            url = users.create_login_url(self.request.uri)
            url_linktext = 'Login'

        template_values = {
            'greetings': greetings,
            'url': url,
            'url_linktext': url_linktext
        }
        
        path = os.path.join(os.path.dirname(__file__), 'index.html')
        self.response.out.write(template.render(path, template_values))

class Guestbook(webapp.RequestHandler):
    def post(self):
        guestbook_name = self.request.get('guestbook_name')
        greeting = Greeting(parent=guestbook_key(guestbook_name))

        if users.get_current_user():
            greeting.author = users.get_current_user()

        greeting.content = self.request.get('content')
        greeting.put()
        self.redirect('/?' + urllib.urlencode({'guestbook_name':
            guestbook_name}))

application = webapp.WSGIApplication(
        [('/', MainPage),
         ('/sign', Guestbook)], 
        debug=True)

def main():
    run_wsgi_app(application)

if __name__ == "__main__":
    main()

